java - 我如何在一个类中拥有 JTextArea，并打印到另一个类中的 JTextArea？

Question

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已关闭 11 年前。

我有两个类。一个用于运行程序，另一个用于作为 GUI。使用简单的 out.print 构建了第一个，但后来我意识到我需要将输出放在 JTextArea 中而不是控制台。所以我为它准备了一个 gui，但不知道是否将该 gui 放入我的运行类中，还是从运行类中调用我的 gui。这是运行代码

import com.jcraft.jsch.*;
import java.awt.*;
import javax.swing.*;
import javax.swing.JTextArea;
import java.util.Vector;

public class Sftp{
static JTextArea guiConsole = new JTextArea(10,10);
  public static void main(String[] arg){

    try{
      JSch jsch=new JSch();

      String host=null;
      if(arg.length>0){
        host=arg[0];
      }
      else{
        host=JOptionPane.showInputDialog("Enter username@hostname",
                                         System.getProperty("user.name")+
                                         "@localhost"); 
      }
      String user=host.substring(0, host.indexOf('@'));
      host=host.substring(host.indexOf('@')+1);
      int port=22;

      Session session=jsch.getSession(user, host, port);

      // username and password will be given via UserInfo interface.
      UserInfo ui=new MyUserInfo();
      session.setUserInfo(ui);

      session.connect();

      Channel channel=session.openChannel("sftp");
      channel.connect();
      ChannelSftp c=(ChannelSftp)channel;

      java.io.InputStream in=System.in;


      java.util.Vector<String> cmds=new java.util.Vector<String>();
      byte[] buf=new byte[1024];
      int i;
      String str;
      int level=0;

      while(true){
    guiConsole.append("sftp> ");
    cmds.removeAllElements();
        i=in.read(buf, 0, 1024);
    if(i<=0)break;

        i--;
        if(i>0 && buf[i-1]==0x0d)i--;
        //str=new String(buf, 0, i);
        //guiConsole.append("|"+str+"|");
    int s=0;
    for(int ii=0; ii<i; ii++){
          if(buf[ii]==' '){
            if(ii-s>0){ cmds.addElement(new String(buf, s, ii-s)); }
        while(ii<i){if(buf[ii]!=' ')break; ii++;}
        s=ii;
      }
    }
    if(s<i){ cmds.addElement(new String(buf, s, i-s)); }
    if(cmds.size()==0)continue;

    String cmd=cmds.elementAt(0);
    if(cmd.equals("quit")){
          c.quit();
      break;
    }
    if(cmd.equals("exit")){
          c.exit();
      break;
    }
    if(cmd.equals("rekey")){
      session.rekey();
      continue;
    }
    if(cmd.equals("compression")){
          if(cmds.size()<2){
        guiConsole.append("compression level: "+level);
            continue;
      }
      try{
        level=Integer.parseInt(cmds.elementAt(1));
        if(level==0){
          session.setConfig("compression.s2c", "none");
          session.setConfig("compression.c2s", "none");
        }
        else{
              session.setConfig("compression.s2c", "zlib@openssh.com,zlib,none");
              session.setConfig("compression.c2s", "zlib@openssh.com,zlib,none");
        }
      }
      catch(Exception e){}
          session.rekey();
      continue;
    }
    if(cmd.equals("cd") || cmd.equals("lcd")){
          if(cmds.size()<2) continue;
      String path=cmds.elementAt(1);
      try{
        if(cmd.equals("cd")) c.cd(path);
        else c.lcd(path);
      }
      catch(SftpException e){
        guiConsole.append(e.toString());
      }
      continue;
    }
    if(cmd.equals("rm") || cmd.equals("rmdir") || cmd.equals("mkdir")){
          if(cmds.size()<2) continue;
      String path=cmds.elementAt(1);
      try{
        if(cmd.equals("rm")) c.rm(path);
        else if(cmd.equals("rmdir")) c.rmdir(path);
        else c.mkdir(path);
      }
      catch(SftpException e){
        guiConsole.append(e.toString());
      }
      continue;
    }
    if(cmd.equals("chgrp") || cmd.equals("chown") || cmd.equals("chmod")){
          if(cmds.size()!=3) continue;
      String path=cmds.elementAt(2);
      int foo=0;
      if(cmd.equals("chmod")){
            byte[] bar=cmds.elementAt(1).getBytes();
            int k;
            for(int j=0; j<bar.length; j++){
              k=bar[j];
          if(k<'0'||k>'7'){foo=-1; break;}
          foo<<=3;
          foo|=(k-'0');
        }
        if(foo==-1)continue;
      }
      else{
        try{foo=Integer.parseInt(cmds.elementAt(1));}
        catch(Exception e){continue;}
      }
      try{
        if(cmd.equals("chgrp")){ c.chgrp(foo, path); }
        else if(cmd.equals("chown")){ c.chown(foo, path); }
        else if(cmd.equals("chmod")){ c.chmod(foo, path); }
      }
      catch(SftpException e){
        guiConsole.append(e.toString());
      }
      continue;
    }
    if(cmd.equals("pwd") || cmd.equals("lpwd")){
           str=(cmd.equals("pwd")?"Remote":"Local");
       str+=" working directory: ";
          if(cmd.equals("pwd")) str+=c.pwd();
      else str+=c.lpwd();
      guiConsole.append(str);
      continue;
    }
    if(cmd.equals("ls") || cmd.equals("dir")){
      String path=".";
      if(cmds.size()==2) path=cmds.elementAt(1);
      try{
       Vector vv=c.ls(path);
        if(vv!=null){
          for(int ii=0; ii<vv.size(); ii++){
          //    guiConsole.appendln(vv.elementAt(ii).toString());

                Object obj=vv.elementAt(ii);
                if(obj instanceof com.jcraft.jsch.ChannelSftp.LsEntry){
                   guiConsole.append(((com.jcraft.jsch.ChannelSftp.LsEntry)obj).getLongname());
                }

          }
        }
      }
      catch(SftpException e){
        guiConsole.append(e.toString());
      }
      continue;
    }
    if(cmd.equals("lls") || cmd.equals("ldir")){
      String path=".";
      if(cmds.size()==2) path=cmds.elementAt(1);
      try{
        java.io.File file=new java.io.File(path);
        if(!file.exists()){
          guiConsole.append(path+": No such file or directory");
              continue; 
            }
        if(file.isDirectory()){
          String[] list=file.list();
          for(int ii=0; ii<list.length; ii++){
        guiConsole.append(list[ii]);
          }
          continue;
        }
        guiConsole.append(path);
      }
      catch(Exception e){
        guiConsole.append(e.toString());
      }
      continue;
    }
    if(cmd.equals("get") || 
       cmd.equals("get-resume") || cmd.equals("get-append") || 
       cmd.equals("put") || 
       cmd.equals("put-resume") || cmd.equals("put-append")
       ){
      if(cmds.size()!=2 && cmds.size()!=3) continue;
      String p1=cmds.elementAt(1);
          //  String p2=p1;
      String p2=".";
      if(cmds.size()==3)p2=cmds.elementAt(2);
      try{
        SftpProgressMonitor monitor=new MyProgressMonitor();
        if(cmd.startsWith("get")){
          int mode=ChannelSftp.OVERWRITE;
          if(cmd.equals("get-resume")){ mode=ChannelSftp.RESUME; }
          else if(cmd.equals("get-append")){ mode=ChannelSftp.APPEND; } 
          c.get(p1, p2, monitor, mode);
        }
        else{ 
          int mode=ChannelSftp.OVERWRITE;
          if(cmd.equals("put-resume")){ mode=ChannelSftp.RESUME; }
          else if(cmd.equals("put-append")){ mode=ChannelSftp.APPEND; } 
          c.put(p1, p2, monitor, mode); 
        }
      }
      catch(SftpException e){
        guiConsole.append(e.toString());
      }
      continue;
    }
    if(cmd.equals("ln") || cmd.equals("symlink") || cmd.equals("rename")){
          if(cmds.size()!=3) continue;
      String p1=cmds.elementAt(1);
      String p2=cmds.elementAt(2);
      try{
        if(cmd.equals("rename")) c.rename(p1, p2);
        else c.symlink(p1, p2);
      }
      catch(SftpException e){
        guiConsole.append(e.toString());
      }
      continue;
    }
    if(cmd.equals("stat") || cmd.equals("lstat")){
          if(cmds.size()!=2) continue;
      String p1=cmds.elementAt(1);
      SftpATTRS attrs=null;
      try{
        if(cmd.equals("stat")) attrs=c.stat(p1);
        else attrs=c.lstat(p1);
      }
      catch(SftpException e){
        guiConsole.append(e.toString());
      }
      if(attrs!=null){
            guiConsole.append(attrs.toString());
      }
      else{
      }
      continue;
    }
    if(cmd.equals("readlink")){
          if(cmds.size()!=2) continue;
      String p1=cmds.elementAt(1);
      String filename=null;
      try{
        filename=c.readlink(p1);
            guiConsole.append(filename);
      }
      catch(SftpException e){
        guiConsole.append(e.toString());
      }
      continue;
    }
    if(cmd.equals("realpath")){
          if(cmds.size()!=2) continue;
      String p1=cmds.elementAt(1);
      String filename=null;
      try{
        filename=c.realpath(p1);
            guiConsole.append(filename);
      }
      catch(SftpException e){
          guiConsole.append(e.toString());
      }
      continue;
    }
    if(cmd.equals("version")){
      guiConsole.append("SFTP protocol version "+c.version());
      continue;
    }
    if(cmd.equals("help") || cmd.equals("?")){
      guiConsole.append(help);
      continue;
    }
        guiConsole.append("unimplemented command: "+cmd);
      }
      session.disconnect();
    }
    catch(Exception e){
      guiConsole.append(e.toString());
    }
    System.exit(0);
  }

  public static class MyUserInfo implements UserInfo, UIKeyboardInteractive{
    public String getPassword(){ return passwd; }
    public boolean promptYesNo(String str){
      Object[] options={ "yes", "no" };
      int foo=JOptionPane.showOptionDialog(null, 
             str,
             "Warning", 
             JOptionPane.DEFAULT_OPTION, 
             JOptionPane.WARNING_MESSAGE,
             null, options, options[0]);
       return foo==0;
    }

    String passwd;
    JTextField passwordField=(JTextField)new JPasswordField(20);

    public String getPassphrase(){ return null; }
    public boolean promptPassphrase(String message){ return true; }
    public boolean promptPassword(String message){
      Object[] ob={passwordField}; 
      int result=
      JOptionPane.showConfirmDialog(null, ob, message,
                    JOptionPane.OK_CANCEL_OPTION);
      if(result==JOptionPane.OK_OPTION){
    passwd=passwordField.getText();
    return true;
      }
      else{ return false; }
    }
    public void showMessage(String message){
      JOptionPane.showMessageDialog(null, message);
    }
    final GridBagConstraints gbc = 
      new GridBagConstraints(0,0,1,1,1,1,
                             GridBagConstraints.NORTHWEST,
                             GridBagConstraints.NONE,
                             new Insets(0,0,0,0),0,0);
    private Container panel;
    public String[] promptKeyboardInteractive(String destination,
                                              String name,
                                              String instruction,
                                              String[] prompt,
                                              boolean[] echo){
      panel = new JPanel();
      panel.setLayout(new GridBagLayout());

      gbc.weightx = 1.0;
      gbc.gridwidth = GridBagConstraints.REMAINDER;
      gbc.gridx = 0;
      panel.add(new JLabel(instruction), gbc);
      gbc.gridy++;

      gbc.gridwidth = GridBagConstraints.RELATIVE;

      JTextField[] texts=new JTextField[prompt.length];
      for(int i=0; i<prompt.length; i++){
        gbc.fill = GridBagConstraints.NONE;
        gbc.gridx = 0;
        gbc.weightx = 1;
        panel.add(new JLabel(prompt[i]),gbc);

        gbc.gridx = 1;
        gbc.fill = GridBagConstraints.HORIZONTAL;
        gbc.weighty = 1;
        if(echo[i]){
          texts[i]=new JTextField(20);
        }
        else{
          texts[i]=new JPasswordField(20);
        }
        panel.add(texts[i], gbc);
        gbc.gridy++;
      }

      if(JOptionPane.showConfirmDialog(null, panel, 
                                       destination+": "+name,
                                       JOptionPane.OK_CANCEL_OPTION,
                                       JOptionPane.QUESTION_MESSAGE)
         ==JOptionPane.OK_OPTION){
        String[] response=new String[prompt.length];
        for(int i=0; i<prompt.length; i++){
          response[i]=texts[i].getText();
        }
    return response;
      }
      else{
        return null;  // cancel
      }
    }
  }

/*
  public static class MyProgressMonitor implements com.jcraft.jsch.ProgressMonitor{
    JProgressBar progressBar;
    JFrame frame;
    long count=0;
    long max=0;

    public void init(String info, long max){
      this.max=max;
      if(frame==null){
        frame=new JFrame();
    frame.setSize(200, 20);
        progressBar = new JProgressBar();
      }
      count=0;

      frame.setTitle(info);
      progressBar.setMaximum((int)max);
      progressBar.setMinimum((int)0);
      progressBar.setValue((int)count);
      progressBar.setStringPainted(true);

      JPanel p=new JPanel();
      p.add(progressBar);
      frame.getContentPane().add(progressBar);
      frame.setVisible(true);
      System.guiConsole.appendln("!info:"+info+", max="+max+" "+progressBar);
    }
    public void count(long count){
      this.count+=count;
      System.guiConsole.appendln("count: "+count);
      progressBar.setValue((int)this.count);
    }
    public void end(){
      System.guiConsole.appendln("end");
      progressBar.setValue((int)this.max);
      frame.setVisible(false);
    }
  }
*/

  public static class MyProgressMonitor implements SftpProgressMonitor{
    ProgressMonitor monitor;
    long count=0;
    long max=0;
    public void init(int op, String src, String dest, long max){
      this.max=max;
      monitor=new ProgressMonitor(null, 
                                  ((op==SftpProgressMonitor.PUT)? 
                                   "put" : "get")+": "+src, 
                                  "",  0, (int)max);
      count=0;
      percent=-1;
      monitor.setProgress((int)this.count);
      monitor.setMillisToDecideToPopup(1000);
    }
    private long percent=-1;
    public boolean count(long count){
      this.count+=count;

      if(percent>=this.count*100/max){ return true; }
      percent=this.count*100/max;

      monitor.setNote("Completed "+this.count+"("+percent+"%) out of "+max+".");     
      monitor.setProgress((int)this.count);

      return !(monitor.isCanceled());
    }
    public void end(){
      monitor.close();
    }
  }

  private static String help =
"      Available commands:\n"+
"      * means unimplemented command.\n"+
"cd path                       Change remote directory to 'path'\n"+
"lcd path                      Change local directory to 'path'\n"+
"chgrp grp path                Change group of file 'path' to 'grp'\n"+
"chmod mode path               Change permissions of file 'path' to 'mode'\n"+
"chown own path                Change owner of file 'path' to 'own'\n"+
"help                          Display this help text\n"+
"get remote-path [local-path]  Download file\n"+
"get-resume remote-path [local-path]  Resume to download file.\n"+
"get-append remote-path [local-path]  Append remote file to local file\n"+
"*lls [ls-options [path]]      Display local directory listing\n"+
"ln oldpath newpath            Symlink remote file\n"+
"*lmkdir path                  Create local directory\n"+
"lpwd                          Print local working directory\n"+
"ls [path]                     Display remote directory listing\n"+
"*lumask umask                 Set local umask to 'umask'\n"+
"mkdir path                    Create remote directory\n"+
"put local-path [remote-path]  Upload file\n"+
"put-resume local-path [remote-path]  Resume to upload file\n"+
"put-append local-path [remote-path]  Append local file to remote file.\n"+
"pwd                           Display remote working directory\n"+
"stat path                     Display info about path\n"+
"exit                          Quit sftp\n"+
"quit                          Quit sftp\n"+
"rename oldpath newpath        Rename remote file\n"+
"rmdir path                    Remove remote directory\n"+
"rm path                       Delete remote file\n"+
"symlink oldpath newpath       Symlink remote file\n"+
"readlink path                 Check the target of a symbolic link\n"+
"realpath path                 Canonicalize the path\n"+
"rekey                         Key re-exchanging\n"+
"compression level             Packet compression will be enabled\n"+
"version                       Show SFTP version\n"+
"?                             Synonym for help";
}

这是图形用户界面。

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class CommandBox extends JPanel implements ActionListener {
protected JTextField textField;
protected JTextArea textArea;
private final static String newline = "\n";

public CommandBox() {
    super(new GridBagLayout());

    textField = new JTextField(20);
    textField.addActionListener(this);

    textArea = new JTextArea(5, 20);
    textArea.setEditable(false);
    JScrollPane scrollPane = new JScrollPane(textArea);

    //Add Components to this panel.
    GridBagConstraints c = new GridBagConstraints();
    c.gridwidth = GridBagConstraints.REMAINDER;

    c.fill = GridBagConstraints.HORIZONTAL;
    add(textField, c);

    c.fill = GridBagConstraints.BOTH;
    c.weightx = 1.0;
    c.weighty = 1.0;
    add(scrollPane, c);
}

public void actionPerformed(ActionEvent evt) {
    String text = textField.getText();
    textArea.append(text + newline);
    textField.selectAll();

    //Make sure the new text is visible, even if there
    //was a selection in the text area.
    textArea.setCaretPosition(textArea.getDocument().getLength());
}

private static void createAndShowGUI() {
    //Create and set up the window.
    JFrame frame = new JFrame("VSI");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    //Add contents to the window.
    frame.add(new CommandBox());

    //Display the window.
    frame.pack();
    frame.setVisible(true);
}

public static void main(String[] args) {
    //Schedule a job for the event dispatch thread:
    //creating and showing this application's GUI.
    javax.swing.SwingUtilities.invokeLater(new Runnable() {
        public void run() {
            createAndShowGUI();
        }
    });
}
}

我的问题是你会做什么。你们是程序员，比我更有技术和知识。

Answer 1

如果您在 GUI 类中为 JTextArea 创建 getter，则可以通过在要输出文本的类中创建一个对象来将文本设置到 JTextArea 。请参阅下面的示例:

CommandBox commandBox = new CommandBox();
commandBox.getTextArea().setText("Your text");